Determining if a partition is initiator-distinguishable from its following set

In a partitioned type, a partition is initiator-distinguishable from its following set if:

• The type of a partition has an initiator and
• The following set is empty or
• The type of the partition is initiator-distinguishable from each partition in its following set and the following set of a partition is the type of each partition that may follow.

Type trees are analyzed to determine if partitions are initiator-distinguishable. Each partitioned type is analyzed to determine if its partitions are initiator-distinguishable.